I'm going to keep this quick and simple, Malz in my opinion is one of the most under rated ap carries in the game, of course he specializes in a 1 v 1 scenario but a well played/ understood malz can benefit a team in any scenario ... I only wish to make this guide because I see so many people play malz horrendously and though I might not be godlike with him, I can gladly say that I have the skills with this AP Champ to win most games

- i am going to be going under the impression that you will be choosing to go mid -

Pros

Great Sustaining in lane

Excellent 1 v 1
Killer combo
Easy CS
The ability to face roll your keyboard to kill

Cons

Highly Vulnerable during ult
No one likes you
Be afraid of the QSS and the BV

The reason why I've taking 21/9/0 instead of 21/0/9 is because if you understand the mechanics of a malz, the amount of extra mana isn't as beneficial as apposed to the extra hp that can keep you alive

Basic magic pen, cdr, bonus ap at the start of the game and mp5 for extra spamming

The regular ignite flash

Your dot (E) is your go to ability for CS and damage , max it first
The point in W at level 4 is your extra punch for your ult combo
The rest is generic stuff to remember
After dot max out your silence as it does killer damage and lastly your void zone

Starting off with Boots + 3x Health pots is a great way to sustain your lane, you can go for a mana potion if you feel unsafe about spamming your abilities but my preference is this

- on your first time back you should hopefully get your sorc boots

- from here on out the build can vary depending on the situation
i personally do not go for any major mana items such as a tear or RoA - through my hundreds of games as malz i have not had the need for extra mana that a blue buff cannot support or that i cannot get back with the use of my e

- I like to get the blasting wand and negatron cloak as early as possible, though i dont get the abyssal first as my core build, the aid of the cloak is very helpful throughout the mid game

- once i gain enough gold i get my large rod and build to my deathcap ... from here your next item can be taken in 2 ways
- if i am being focused hard or need reassurance during a fight, I build my abyssal next other wise I go for a void staff

- in late game a malz combo should be able to shut down most enemy carries and have heavy poke damage on all non tanks, the item's I usually build work for this ...

- the different scenarios that you guys can build from my experience are as follows
- a deathfire grasp can be the icing on the cake when it comes to killing an enemy carry due to the massive damage under most circumstances
- though i dont use it , a rylais can be effective to help your team but understand that malz is designed to be a OHKO champ
- if the abyssal isn't your thing and you need more mr or a safety net, a Banshee's veil can be useful to surviving

- When you start off the game and put your point in Q , REMEMBER to charge your voidling = using your q ability 3x

- important notice
- in lane , if you play passive till level 3(ie- not waste your voidling) ... a well timed gank or a q+e+ignite combo can change the tide of the lane, this combo at lvl 3 is one of the most deadliest and easiest to utilize
- your silence can be the catalyst to starting a team fight, it does major damages to most squishies and has a duration that can last long enough to kill most
- with these runes and specs your E will most likely be able to clear a minion wave around level 5
- remember your voidling is a significant part of your offense, it is extremely beneficial to have your voidling ready to cast before your ult combo, early game people might focus on getting mr, but a 14-21 second voidling does significant ad damage
- be cautious of morg's spell shield or a BV/QSS, these items essentially negate the usefulness of your combo, make sure to rid of them before engaging

In the end, this is my first guide, its prob not as detailed or as on par with the other's you'll see but I made this account because I've seen such poor malz players, and questions or comments and i can gladly help ... try it out, its done me good , hopefully it will do you good as well